Journal of Animal Science, Vol 78, Issue 5 1284-1290, Copyright © 2000 by American Society of Animal Science

JOURNAL ARTICLE

Beta-carotene uptake and changes in ovarian steroids and uterine proteins during the estrous cycle in the canine

B. C. Weng, B. P. Chew, T. S. Wong, J. S. Park, H. W. Kim and A. J. Lepine
Department of Animal Sciences, Washington State University, Pullman 99164-6351, USA.

The uptake of beta-carotene by reproductive tissues and the effects of beta-carotene on reproductive function in the dog are unknown. We studied the uptake of beta-carotene by blood, corpus luteum, and uterine endometrium and the role of dietary beta-carotene in influencing ovarian steroid and uterine protein production during the estrous cycle in the dog. Mature female Beagle dogs (n = 56) were fed diets containing 0, 2, 20, or 50 mg of beta-carotene daily for approximately 6 wk before estrus detection. Blood was sampled at regular intervals from estrus through d 45 after ovulation (d 0 = ovulation), when laparotomy was performed. The ovaries were obtained for the isolation of corpus luteum. The uterus was flushed with phosphate-buffered saline and the endometrium obtained by scraping. Beta-carotene was not detectable in plasma, corpus luteum, or endometrium of unsupplemented dogs. However, beta-carotene and alpha-carotene in plasma, corpus luteum, and uterine endometrium increased in a dose-dependent manner. Alpha-carotene made up a high percentage of total carotenoids even though the alpha-carotene content in the dietary source was very low. Dogs fed 50 mg of beta-carotene had significantly higher concentrations of plasma progesterone between d 12 and 26 compared with unsupplemented dogs. Dietary beta-carotene did not influence plasma estradiol-17beta and total uterine proteins. Therefore, beta-carotene is absorbed into plasma, corpus luteum, and uterine endometrium of dogs. Furthermore, dietary beta-carotene increased plasma progesterone concentrations during the estrous cycle. It is possible that dietary beta-carotene may improve reproductive function in the canine.

This article has been cited by other articles:

				J. Raila, C. Gomez, and F. J. Schweigert The Ferret as a Model for Vitamin A Metabolism in Carnivores J. Nutr., June 1, 2002; 132(6): 1787S - 1789. [Abstract] [Full Text] [PDF]